• Knowledge Management Research
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• v.15 no.3
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• pp.169-188
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• 2014

Big data seems to change knowledge management system and method of enterprises to large extent. Further, the type of method for utilization of unstructured data including image, v ideo, sensor data a nd text may determine the decision on expansion of knowledge management of the enterprise or government. This paper, in this light, attempts to figure out the prediction model of demands and supply for big data market of Korea trough data mining decision making tree by utilizing text bit data generated for 3 years on web and SNS for expansion of form for knowledge management. The results indicate that the market focused on H/W and storage leading by the government is big data market of Korea. Further, the demanders of big data have been found to put important on attribute factors including interest, quickness and economics. Meanwhile, innovation and growth have been found to be the attribute factors onto which the supplier puts importance. The results of this research show that the factors affect acceptance of big data technology differ for supplier and demander. This article may provide basic method for study on expansion of analysis form of enterprise and connection with its management activities.

• Journal of Korean Society of Forest Science
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• v.94 no.5 s.162
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• pp.313-320
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• 2005

This study was performed in a 38-year-old Mongolian pine (Pinus sylvestris L. var. mongolica Litvin) plantation in northeast China. Data were collected from 5 sample trees with different canopy position ranging in DBH from 14.6 cm to 23.8 cm. Sawn speciments that included the biggest knot were taken from the stem below the living crown. Number and distribution of knots per whorl below the living crown were studied by relative height below living crown (RHBC). A linear model expressed as function of whorl age (AGE), whorl height ($H_k$) and the stem diameter at which the whorl was located ($D_k$) was developed to predict the knot diameter and angle. The number of annual rings in four periods and the width of respective zone alone stem were used as dependant variables to analyze the knot develop phases. In average, the number of years from branch birth to ceased forming rings was 7.8, the branches remained alive for 4.2 years without forming annual rings, and branches were occluded 14.4 years after their death. These results can provide abundance branch and knot information so as to describe current and past tree growth dynamic of Mongolian pine plantation.

• Journal of the Korean Wood Science and Technology
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• v.39 no.4
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• pp.333-343
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• 2011

The yellow poplar is an appropriate species for the age of low carbon green growth, because its absorption rates of ozone is greatly excellent, and also the absorption rates of carbon dioxide causing climate changes is very remarkable. The yellow poplar, which is a kind of rapid growth tree, shows a lack of performance as a structural member, however, it is suitable to use a variety of purposes like furniture materials, interior materials, plywood materials, and so on. In this study, the structural size skin-timbers were made by using the yellow poplar, and the compressive capacity was evaluated, also the numerical model was developed for the various uses. The rectangular shape skin-timber presented a good performance by showing 56.3% residual strength about the solid material. In case of the cylinder shape skin-timber showed a possibility to use diversely as a furniture material, as well as a structural uses, because almost 50% compressive capacity of material even though its residual area rates was 25%. Both rectangular shape and the cylinder shape represented that 'Brooming or end rolling' were the major failure mode, and partly splitting failure mode. The compressive capacity of the rectangular shape which residual area rates was large was higher than the cylinder shape, but it did not show statistical significance about the compressive capacity between them. Thus, it will be possible to use them mixed for a convenience of users. The result of the numerical analysis model was quite similar to actual test of the compressive capacity. Therefore, the yellow poplar can be utilized in the development of various uses by applying numerical analysis model about a variety of shapes and dimensions.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.722-728
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• 2005

The DNA topoismerase I inhibitor ${\beta}-lapachone$, the product of a lapacho tree (Tabebuia avellanedae) from South America, activates a novel apoptotic response in a number of cell lines. In the present report, we investigated the effects of ${\beta}-lapachone$ on the growth of human lung in human non-small-cell-lung-cancer A549 cells. Upon treatment with ${\beta}-lapachone$, a concentration-dependent inhibition of cell viability and cell proliferation was observed as measured by hemocytometer counts and MTT assay. The ${\beta}-lapachone-treated$ cells developed many of the hallmark features of apoptosis, including membrane shrinking, condensation of chromatin and DNA fragmentation. These apoptotic effects of ${\beta}-lapachone$ in A549 cells were associated with a marked induction of pro-apoptotic Bax expression, however the levels of anti-apoptotic Bcl-2 expression were decreased in a dose-dependent manner. Accordingly, elevated amount of cyclin-dependent kinase inhibitor p21 expression accompanied by up-regulation of tumor suppressor p53 was observed. By RT-PCR analyses, decrease in gene expression level of telomerase reverse transcriptase and telomeric repeat binding factor were also observed. Thus, these findings suggest that ${\beta}-lapachone$ may be a potential anti-cancer therapeutics for the control of human lung cancer cell model.

• Journal of Forest and Environmental Science
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• v.27 no.3
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• pp.135-141
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• 2011

The present study was carried out from September 2007 to February 2008 in Umfakarin natural forest reserve, South Kordofan, Sudan. The objective was to analyze the effect of different management strategies on yield of gum talha from Acacia seyal. A total of 493 single target trees were selected, based on their diameters, and assigned to tapping treatments in three different stand densities (making a total of nine treatments per stand density). The treatments are as follows: tapping date with three levels (first of October, 15 October and first of November) and two levels of local tapping tools (sonki, and makmak). Untapped trees were used as control. The first picking of gum was started fifteen days after tapping while the subsequent pickings were done in intervals of fifteen days. Yield per tree throughout the season was obtained by summing up the gum yield from all pickings. Yield throughout the season (from first to the last picking) were analyzed. General linear model (GLM) was used to test the effect of different tapping treatments on the yield of gum talha. Post hoc test after analysis of variance (ANOVA) based on Scheffe test was performed to examine the differences in gum yield as a result of different management strategies. The results showed that tapping has a significant influence on gum yield. Analysis of pick-to-pick yield indicated that only three treatments in dense stand density showed a decreasing pattern while the rest of treatments either have constant or unclear patterns. The results of the present study were based on a single season data and that may underscore the real effect of Acacia seyal stands' management strategies on gum talha yield. Conducting gum yield experiments in permanent trial plots are highly recommended in order to analyze gum yield of seasonal time series.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.669-681
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• 2023

Studies have tried to apply remote sensing technology, a non-destructive survey method, instead of the existing destructive survey, which requires relatively large labor input and a long time to estimate chlorophyll content, which is an important indicator for evaluating the growth of fruit trees. This study was conducted to non-destructively evaluate the chlorophyll content of pear tree leaves using unmanned aerial vehicle-based hyperspectral imagery for two years(2021, 2022). The reflectance of the single bands of the pear tree canopy extracted through image processing was band rationed to minimize unstable radiation effects depending on time changes. The estimation (calibration and validation) models were developed using machine learning algorithms of elastic-net, k-nearest neighbors(KNN), and support vector machine with band ratios as input variables. By comparing the performance of estimation models based on full band ratios, key band ratios that are advantageous for reducing computational costs and improving reproducibility were selected. As a result, for all machine learning models, when calibration of coefficient of determination (R²)≥0.67, root mean squared error (RMSE)≤1.22 ㎍/cm², relative error (RE)≤17.9% and validation of R²≥0.56, RMSE≤1.41 ㎍/cm², RE≤20.7% using full band ratios were compared, four key band ratios were selected. There was relatively no significant difference in validation performance between machine learning models. Therefore, the KNN model with the highest calibration performance was used as the standard, and its key band ratios were 710/714, 718/722, 754/758, and 758/762 nm. The performance of calibration showed R²=0.80, RMSE=0.94 ㎍/cm², RE=13.9%, and validation showed R²=0.57, RMSE=1.40 ㎍/cm², RE=20.5%. Although the performance results based on validation were not sufficient to estimate the chlorophyll content of pear tree leaves, it is meaningful that key band ratios were selected as a standard for future research. To improve estimation performance, it is necessary to continuously secure additional datasets and improve the estimation model by reproducing it in actual orchards. In future research, it is necessary to continuously secure additional datasets to improve estimation performance, verify the reliability of the selected key band ratios, and upgrade the estimation model to be reproducible in actual orchards.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.3
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• pp.113-122
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• 2007

The rapid growth of aerial survey and remote sensing technology has enabled the rapid acquisition of very large amounts of geographic data, which should be analyzed using real-time visualization technology. The level of detail(LOD) algorithm is one of the most important elements for realizing real-time visualization. We chose the triangulated irregular network (TIN) method to generate normalized digital elevation model(DEM) data. First, we generated TIN data using contour lines obtained from a two-dimensional(2D) digital map and created a 2D grid array fitting the size of the area. Then, we generated normalized DEM data by calculating the intersection points between the TIN data and the points on the 2D grid array. We used constrained Delaunay triangulation(CDT) and ray-triangle intersection algorithms to calculate the intersection points between the TIN data and the points on the 2D grid array in each step. In addition, we simulated a three-dimensional(3D) terrain model based on normalized DEM data with real-time visualization using a Microsoft Visual C++ 6.0 program in the DirectX API library and a quad-tree LOD algorithm.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.1
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• pp.103-118
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• 2018

Ecosystems in subalpine regions are recognized as areas vulnerable to climatic changes because rainfall and the possibility of flora migration are very low due to the characteristics of topography in the regions. In this context, habitat niche was formulated for representative species of arbors in subalpine regions in order to understand the effects of climatic changes on alpine arbor ecosystems. The current potential habitats were modeled as future change areas according to the climatic change scenarios. Based on the growth conditions and environmental characteristics of the habitats, the study was conducted to identify direct and indirect causes affecting the habitat reduction of Abies nephrolepis. Diverse model algorithms for explanation of the relationship between the emergence of biological species and habitat environments were reviewed to construct the environmental data suitable for the six models(GLM, GAM, RF, MaxEnt, ANN, and SVM). Weights determined through TSS were applied to the six models for ensemble in an attempt to minimize the uncertainty of the models. Based on the current climate determined by averaging the climates over the past 30years(1981~2010) and the HadGEM-RA model was applied to fabricate bioclimatic variables for scenarios RCP 4.5 and 8.5 on the near and far future. The results of models of the alpine region tree species studied were put together and evaluated and the results indicated that a total of eight national parks such as Mt. Seorak, Odaesan, and Hallasan would be mainly affected by climatic changes. Changes in the Baekdudaegan reserves were analyzed and in the results, A. nephrolepis was predicted to be affected the most in the RCP8.5. The results of analysis as such are expected to be finally utilizable in the survey of biological species in the Korean peninsula, restoration and conservation strategies considering climatic changes as the analysis identified the degrees of impacts of climatic changes on subalpine region trees in Korean peninsula with very high conservation values.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.198-205
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• 2015

The aim of this study was to provide the basic design parameters for developing logging residue compression machines by investigating compressive deformation characteristics of different types of logging residues. To achieve these objectives, Pinus rigida, Pinus koraensis and Quercus mongolica were selected as specimens, and compression-deformation tests by UTM(universial testing machine) were conducted. The experimental dataset were used to set up the model based on the compression-deformation ratio in the form of exponential function. The results showed that stress coefficient in terms of mechanical properties of logging residues was decreased, whereas strain coefficient tended to be increased as the number of compression increased at target density of $350kg/m^3$ and $400kg/m^3$. The model presented that the required stress was decreased as the number of compression increased, and the stress growth rate was swelled compared to the change of the deformation rate. Therefore, it showed that proper initial compression force was a significant variable in order to achieve the target density of logging residue.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.387-396
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• 2005

Having employed the transitional probability model based on Markov chain, the study was carried out to examine successional trends for community types in the natural deciduous forest of Mt. Jumbong. The species composition of oncoming generation in overstory was estimated from that of mid-story, and the species composition in mid-story was based upon that of understory. Successional trend for each community was predicted from the reorganized probability matrix of tree replacement by the square of climax index, which was evaluated by the factors of light absorption, reproduction, and wood quality. As the result of analysis, following table shows the oncoming generation of steady state and dominant species in overstory and mid-story by community types. Even though Acer pseudo-sieboldianum and Carpinus cordata could hardly reach the canopy layer due to the intrinsic growth form, these species were predicted to maintain high compositional ratio so as to play an important ecological role in the study forest ecosystem.